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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
ZWO ASI220MM Mini Mono Guide Camera

ZWO ASI220MM Mini Mono Guide Camera

by ZWO
SKU ZWO-ASI220MINI
$249.00 - $249.00
$249.00
$249.00 - $249.00
$249.00
Price Match Policy!
  • 2.1 Megapixel Resolution (1920 x 1080)
  • 4.0µm Pixel Size
  • 92% Peak Quantum Efficiency
  • 0.6e Minimum Read Noise
  • 1/1.8" Monochrome CMOS Sensor
1 in stock
Qualifies for FREE Shipping in CONUS on orders over $350.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • ZWO ASI220MM Mini Monochrome Astronomy Camera

    The ZWO ASI220MM Mini Mono Guide Camera establishes a new standard for autoguiding sensitivity, combining a 2.1 MP sensor with a 1920 x 1080 resolution for precise tracking. Its 4µm pixels achieve an exceptional 92% peak quantum efficiency, ensuring faint guide stars are captured reliably in short exposures. With an extremely low read noise floor of just 0.6e and a full well capacity of 8.78ke, the sensor maintains a high signal-to-noise ratio, while the USB 2.0 interface delivers a steady 14 FPS at full resolution.

    92% Peak QE from a 1/1.8" Monochrome Sensor

    The core of the ASI220MM Mini's guiding capability is its remarkable sensitivity. A peak Quantum Efficiency of 92% means the camera converts nearly every incoming photon from a guide star into usable signal. This efficiency, combined with the light-gathering advantage of a monochrome sensor, allows you to use fainter stars for guiding and achieve a solid lock with shorter, more frequent exposures—reducing the impact of seeing conditions on your tracking accuracy.

    4.0µm Pixels and 0.6e Read Noise for Faint Guide Stars

    The camera's 4.0µm pixels offer a significant sensitivity advantage over smaller-pixel designs, capturing more light per pixel and improving performance on long focal length guide scopes or Off-Axis Guiders (OAGs). This is paired with an exceptionally low read noise of 0.6e at high gain. This combination ensures that the faint signal from a guide star is not lost in electronic noise, providing your guiding software with high-quality data for sub-pixel corrections.

    ASI220MM Mini vs. ASI290MM Mini: A Guiding Comparison

    When choosing a guide camera, the ASI220MM Mini is often compared to its sibling, the ASI290MM Mini. The best choice depends entirely on your optical setup.

    • ZWO ASI290MM Mini: With smaller 2.9µm pixels, the ASI290MM Mini achieves a finer image scale. This makes it an excellent match for shorter focal length guide scopes (under 400mm), where it can deliver higher-resolution centroids for guiding calculations.
    • ZWO ASI220MM Mini: The larger 4.0µm pixels, higher 92% QE, and lower 0.6e read noise give the ASI220MM Mini a raw sensitivity advantage. It will detect fainter stars in any given field, making it the superior choice for longer focal length systems or OAGs where guide stars can be sparse or dim.

    8.5mm Back Focus and 1.25" Format for OAG and Guide Scopes

    Designed for easy integration, the ASI220MM Mini features a standard 1.25" body and a slim profile with just 8.5mm of back focus, making it ideal for Off-Axis Guiders where minimizing intrusion into the main light path is critical. The camera includes both a standard ST-4 guide port for direct connection to your mount and a USB 2.0 Type-C port for data and power. While the USB 2.0 interface limits the camera to 14 FPS, this rate is more than sufficient for high-performance autoguiding.

  • What is the main advantage of the ZWO ASI220MM Mini for autoguiding?

    The primary advantage of the ASI220MM Mini is its raw sensitivity. The combination of 4.0µm pixels, a 92% peak Quantum Efficiency, and an extremely low 0.6e read noise allows it to detect and lock onto fainter guide stars than many other cameras, which is critical when using an Off-Axis Guider or imaging in star-poor regions of the sky.

    How does the ASI220MM Mini perform with an Off-Axis Guider (OAG) on an 8" f/10 SCT?

    The ASI220MM Mini is an excellent choice for an f/10 SCT with an OAG. The long focal length of the telescope makes finding bright guide stars challenging. The camera's high sensitivity and large pixels are ideal for picking up dimmer stars from the edge of the corrected field, ensuring you can almost always find a suitable star to guide on.

    Is the ASI220MM Mini a good replacement for the older ASI290MM Mini?

    It's less a replacement and more an alternative for different use cases. The ASI220MM Mini is superior for longer focal length systems due to its higher sensitivity and larger pixels. The ASI290MM Mini remains an excellent choice for shorter focal length guide scopes where its smaller pixels provide better sampling and resolution.

    Why is the 92% Quantum Efficiency of the ASI220MM Mini significant?

    Quantum Efficiency (QE) measures how effectively the sensor converts photons (light) into electrons (signal). A QE of 92% means that for every 100 photons that hit a pixel, 92 are recorded. This extremely high efficiency allows the camera to build up a strong signal from a faint guide star in a very short exposure, leading to more responsive and accurate guiding.

    Can I use the ZWO ASI220MM Mini for deep-sky imaging of galaxies like M51?

    No, the ASI220MM Mini is not designed for long-exposure deep-sky imaging. It is an uncooled camera with a maximum exposure time of 10 seconds. Without active cooling, thermal noise would overwhelm the signal on the multi-minute exposures required for faint objects like the Whirlpool Galaxy (M51). Its purpose is strictly for autoguiding and potentially some basic planetary or lunar imaging.

    I'm trying to guide on the faint stars around the North American Nebula (NGC 7000). Are the 4.0µm pixels of the ASI220MM Mini a benefit?

    Yes, absolutely. The region around the North American Nebula (NGC 7000) is dense with stars, but many can be faint or reddened by dust. The ASI220MM Mini's large 4.0µm pixels and high sensitivity are a distinct benefit here, as they will pull in more signal from these fainter background stars, giving you more options for a stable guide lock while framing the nebula.

  • SKU ZWO-ASI220MINI
    Camera Series ZWO ASI290
    Sensor 1/1.8" FSI CMOS
    Color/Mono Monochrome
    Cooling Uncooled
    Resolution 1920 x 1080 (2.1 MP)
    Pixel Size 4.0 µm
    Sensor Dimensions 7.68 mm x 4.32 mm
    Sensor Diagonal 8.81 mm
    Peak Quantum Efficiency (QE) 92%
    Full Well Capacity 8.78ke-
    Read Noise 0.6e to 3.2e
    Bit Depth 12-bit
    Max Frame Rate 14 FPS
    Minimum Exposure 32 µs
    Maximum Exposure 10 s
    Shutter Type Electronic Rolling Shutter
    Amp Glow Control No
    Computer Interface USB 2.0
    Guide Port ST-4
    Back Focus 8.5 mm
    Telescope Connection 1.25" Nosepiece
    Protective Window AR Coated
    Operating Temperature -5°C to 50°C
    Operating Humidity 0% to 80%
    Weight 0.3 lbs
    OS Compatibility WIN7/8/10 32/64-bit, Linux, Mac

    • ASI220MM Mini Camera

      × 1

    • 1.25" Cover

      × 1

    • 1.25" Extender

      × 1

    • M28.5-CS Adapter

      × 1

    • ST4 Cable

      × 1

    • 0.5m USB 2.0 Type-C Cable

      × 1

    • 2m USB 2.0 Type-C Cable

      × 1

    • Quick Guide

      × 1

  • ZWO 2-Year Limited Warranty